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Greg
1-Mar-2019, 17:32
120mm f/6.8 Angulon in a Compur shutter.
Serial # indicates that the lens dates from 1949.
Can someone tell me the actual coverage of this optic? I am seriously thinking of using this lens on my Whole Plate camera.
Thanks...

Dan Fromm
1-Mar-2019, 17:43
Greg, no two people here have quite the same concept of coverage.

Schneider's claims 83 degrees, 211 mm for the 121/6.8 Angulon. My literature doesn' have the 120. That's awfully tight for whole plate. But you know how much image quality you need towards the edges of the frame, and no one else does. Ask the lens whether it can do what you need.

Steve Goldstein
1-Mar-2019, 17:56
My PDF copy of Schneider's 1963 German-language brochure confirms Dan's data of 83 degrees and 211mm at infinity. It also gives the maximum usable format as 13x18cm, roughly the same as 5x7. But as Dan suggests, the lens may or may not suit your needs.

If you really need the coverage you'd be better off with a Super-Angulon, either the older 121mm or the newer 120mm, or the Nikkor-SW or Fujinon-W in the same focal length. They're all bigger and heavier than the plain Angulon and will have a good bit more coverage.

Greg
1-Mar-2019, 18:00
Greg, no two people here have quite the same concept of coverage.

Schneider's claims 83 degrees, 211 mm for the 121/6.8 Angulon. My literature doesn' have the 120. That's awfully tight for whole plate. But you know how much image quality you need towards the edges of the frame, and no one else does. Ask the lens whether it can do what you need.


So agree with your post. A few of my lenses are claimed not to cover the formats that I use them on, but they work for me when aligned on-center to the film back. Sale of the 120mm Angulon was initially "as is" with no returns. Now the seller is offering me a "money back guarantee"... A no brainer here. Will acquire the lens, test it on my 8x10, and keep it or not... will post the results. FYI: My 1962 B&J catalogue lists the 6 1/2" Angulon (I assume they mean the 120mm Angulon) as covering the 6 1/2 x 81/2 format but in the past , I have found their list of wide angle lenses coverages to be very optimistic at best.

Dan Fromm
1-Mar-2019, 18:18
Greg, 25.4*6.5 = 165.1, not 120. You have to do the arithmetic, if only to protect yourself.

Mark Crabtree
1-Mar-2019, 20:53
165 Angulon does sound like what you need for whole plate coverage, though maybe not the view you are wanting. I've used a 90 Angulon on 5x7 in spite of mine not coming close to covering. They do seem to vary in coverage, probably mostly related to the mounting and minimum aperture. They are a lot like a Wide Angle Dagors in that the coverage increases considerably at the smallest stops. Spec for 120 in my literature is also 83 degrees and they say 5x7 with slight movements at f22. So it might do something you are happy with, but I'd still expect black corners at infinity even at f45.

Your whole plate lens choices increase when you get in the 150 to 165 focal length.

Oren Grad
1-Mar-2019, 21:25
Try it. My 210 Angulon in Compound will eke out 11x14 if stopped way down. If the 120 picks up usable coverage in the same way it could be within hailing distance of WP.

Chauncey Walden
2-Mar-2019, 15:11
My 165 Angulon won't make the extreme corners of an 8x10 but will do WP nicely. My 121 f/8 Super Angulon will just cover 8x10. My 120 Angulon is in my 4x5 kit.

Daniel Unkefer
2-Mar-2019, 16:18
Focusing closer and using hyperfocal distance charts will minimally increase Angulon coverage. This is true for images even with infinity subjects. Why focus at infinity and then stop down? You are wasting a lot of depth of focus at the back end. So will stopping down increase the circle in my experience. For much closer shooting the circle becomes quite a bit larger. It comes down to your subject matter and what is acceptable to your tastes. Try it and see. Lens designers don't usually take photos in the field. They make charts and quantify everything. But how does it look to your eye?

I have three 120 f6.8 Angulons and I think they are great for what they are. Small and compact. I have many Angulons in barrels and shutters from 65mm to 210mm and I think they all have their good uses.

Oren Grad
2-Mar-2019, 17:08
All of which means that nobody can tell you for sure. Hence Dan's Standard Advice: "Ask it."

Greg
2-Mar-2019, 17:29
Finally got a chance to shoot an 8x10 test negative with the 120mm f/6.8 Angulon. Stopped down to f/32 and focused on a stop sign about 40 feet away. Figured that was pretty much near the hyperfocal spot to still have infinity in focus. Projected image covers within maybe 3/4 of an inch from the corners of the 8x10 negative. Projected image does indeed cover the whole plate format, but the sharpness approaching the corners is unacceptable. The sharpness cut off is very gradual and not abrupt. Sharpness of the trees in the background (probably a mile away) was excellent.

MAubrey
2-Mar-2019, 17:38
The way the angulon was designed produces fall off of sharpness and vignetting where there is no particularly clear line of demarcation where the image of illumination just ends or where the resolution suddenly goes from sharp to soft. Rather it just sort of slowly fades. This can give the impression of more coverage than is actually there in terms of how well the lens resolves details. That's why you'll often find different eras of Schneider's literature saying it was more coverage or less coverage. Some of the earliest lit says 105 degrees, but that's pretty crazy. Don't assume that'll work. It won't. You'll get a terrible image.


Schneider-Angulon
Extremer Bildwinkel von maximal 105°. Bevorzugte Weitwinkelkonstruktion höchster Lichtstärke. Dreiteiliger Satzanastigmat mit 3 verschiedenen Brennweiten. — Auf Verlangen Sonder-Prospekt.

Because of this situation, it's best to either stick with the more recent official specs (between 80 and 85° coverage) when you use it or do a huge amount of testing and decide for yourself what kind of softness you're comfortable with. Typically, the more you can stop down the better you'll get.

Also beware that, especially in the early angulons, the manufacturing tolerances weren't great and there was lot's of variability in quality...another reason to "Ask the lens," as Dan said.

Mark Crabtree
3-Mar-2019, 09:31
The specs in my brochure (from 1963 I think) show increasing coverage with longer focal lengths. 81 degree for 90mm, 83 for 120mm, 84 for the 165mm, and 85 degrees for the 210mm. Figures seem to be for f22. It makes me wonder if they aren't just applying some minimum resolution limit that goes down as presumed format goes up.

Still, good news that the 120 throws light to the corners whole plate. I wouldn't have expected it but do hear plenty of reports of varying coverage from Angulons over the years. "Unacceptable" corner sharpness sounds fine to me; I know that wild look the Angulons get toward the edges of the image, and I like it. I hope the OP lets us know how his works out for his needs.

Greg
3-Mar-2019, 10:18
The specs in my brochure (from 1963 I think) show increasing coverage with longer focal lengths. 81 degree for 90mm, 83 for 120mm, 84 for the 165mm, and 85 degrees for the 210mm. Figures seem to be for f22. It makes me wonder if they aren't just applying some minimum resolution limit that goes down as presumed format goes up.

Still, good news that the 120 throws light to the corners whole plate. I wouldn't have expected it but do hear plenty of reports of varying coverage from Angulons over the years. "Unacceptable" corner sharpness sounds fine to me; I know that wild look the Angulons get toward the edges of the image, and I like it. I hope the OP lets us know how his works out for his needs.

Whole Plate section of the 8x10 negative. Scan was 8.5 x 6.5 inches at 150. Scan is a lot sharper that the how the attachment looks in this post.

Bernice Loui
3-Mar-2019, 10:55
Some time ago, this image circle chart from the Linhof book was put on LFF.
https://www.largeformatphotography.info/forum/showthread.php?103755-Lens-Image-Circle-Chart-From-Linhoff-Book&highlight=linhof

The 120mm f6.8 Angulon and a rated image circle of 200mm at f22. Not quite enough for 5x7. Yet, many continue to demand from lenses larger image circles than they were designed for.

Do use a 165mm Angulon in barrel as a medium wide for 5x7. It does nicely as it is small and produces GOOD images at f16 and smaller with more than enough camera movement.



Bernice